According to tendencies in mobile information terminals compacter in size with higher performance, high demands are growing for thin bendable flexible printed circuits (FPC). In accordance with these tendencies, it is also expected that the flexible printed circuits are made thinner, lighter, smaller while made in a further fine circuit rule with lower costs. Flexible copper clad laminates (FCCL) of inexpensive laminate type or cast type are currently used for flexible printed circuits, but those are unsuitable for forming finer circuitry or thinner size. To realize further smaller, lighter, and thinner flexible printed circuits as demanded in the market, it is necessary to use, e.g., flexible copper clad laminates of metalizing type in which a metal film is formed, but sputtering for forming a metal film on a film results in high costs, thereby making the costs of the flexible printed circuits high.
As an alternative technology such an expensive sputtering, a method for manufacturing flexible copper clad laminates using a comparatively inexpensive electroless plating method, e.g., see Patent Document #1, has been known. In use of the manufacturing method, a flexible copper clad laminate can be manufactured with the same performance as the flexible copper clad laminate of the on-going metalizing type and with lower costs.